content: // Protocol Buffers - Google's data interchange format
  // Copyright 2008 Google Inc.  All rights reserved.
  // https://developers.google.com/protocol-buffers/
  //
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  //     * Redistributions in binary form must reproduce the above
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  // in the documentation and/or other materials provided with the
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  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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  package com.google.protobuf;
  
  /**
   * <p>Abstract interface for a blocking RPC channel.  {@code BlockingRpcChannel}
   * is the blocking equivalent to {@link RpcChannel}.
   *
   * @author kenton@google.com Kenton Varda
   * @author cpovirk@google.com Chris Povirk
   */
  public interface BlockingRpcChannel {
    /**
     * Call the given method of the remote service and blocks until it returns.
     * {@code callBlockingMethod()} is the blocking equivalent to
     * {@link RpcChannel#callMethod}.
     */
    Message callBlockingMethod(
        Descriptors.MethodDescriptor method,
        RpcController controller,
        Message request,
        Message responsePrototype) throws ServiceException;
  }
  